What artifact do Ezio and Desmond seek in Assassin's Creed II?

Ezio and Desmond seek the Apple of Eden in Assassin's Creed II.

The Apple of Eden is one of the series' Pieces of Eden, advanced artifacts created by the Isu, an ancient civilization that existed before recorded human history in the game's mythology. The artifact can influence human minds and is treated by different groups as a source of extraordinary power.

In Assassin's Creed II, Ezio's Renaissance storyline leads him toward the Apple while he investigates the conspiracy surrounding his family's downfall. Desmond experiences Ezio's memories through the Animus in the modern-day sections, linking the historical search to the continuing Assassin-Templar conflict.

The Apple is not the same object as every other Piece of Eden. The Staff of Eden, Sword of Eden, and Shroud of Eden are separate artifacts with their own histories and abilities. Their shared name often causes them to be incorrectly treated as interchangeable.